British and Chinese companies have struck a deal to build three satellites to map China's growth from space, the BBC's Jonathan Amos reports. The observation spacecraft will help China's local governments do better urban planning, and the deal was so important that it was part of the recent $2.25 billion trade deal between the two countries.

The U.K.'s DMCii provides satellite imagery of stuff on the Earth's surface less than three feet wide; it will build the spacecraft that China's 21AT will control for seven years. The satellites will launch in 2014, and a fourth may launch after that.